Indiana State Board of Animal Health

Quick Facts About Lymphocytic Choriomeningitis Virus (LCMV)

What is LCMV? LCMV is a viral infection in mice, but it can also be carried by other rodents such as hamsters, gerbils and guinea pigs. Infected rodents can pass the disease to humans.

Why is LCMV a concern?A rodent breeding facility in Indiana was diagnosed with LCMV in May 2012. Mice from the infected facility have been distributed to pet stores in Indiana as feeders for reptiles, but may have been purchased by individuals for pets or replacement breeding stock. Rodents that came into contact with the infected mice may have picked up the virus.

Which animals can transmit LCMV?A small percentage of wild house mice have LCMV. The virus has also been found in some breeding populations of mice which can lead to pet or feeder mice having the virus. Some mice can carry this virus their entire lives without showing any signs of illness. Other rodents, like hamsters, gerbils, and guinea pigs, that have contact with mice can also get the virus.

How is LCMV spread to humans?People can get LCMV by handling and being around rodents. Urine, droppings, saliva and nesting materials (animal bedding) of rodents that contain LCMV can spread the virus. The virus can be in the air or around these materials. Breathing this air, or coming into direct contact with these materials then touching the nose, eyes, or mouth, or open skin wounds can cause an infection. The virus is not spread person-to-person. Women who get LCMV when they are pregnant can pass the virus to their unborn babies.

What are the symptoms of LCMV?Most healthy people who get LCMV will not have any symptoms or will only have a mild illness that may include fever, loss of appetite, headache, muscle aches, chills, nausea, and vomiting. Other symptoms that can occur are sore throat, cough, and pain to the joints, chest, testicles, or mouth. Some people may develop a more severe form of disease 1 to 2 weeks after the fever starts. This severe form can cause swelling in the brain that may require hospitalization. A woman who gets LCMV while pregnant may have a miscarriage or a baby with severe birth defects.

What should I do if I think I have LCMV?See your doctor immediately if you think you are sick with LCMV. Tell your doctor if you have been around any wild mice, feeder mice, or pet rodents. Especially if you are pregnant or have a weak immune system. Your doctor can decide if you need to be tested and how best to treat your symptoms.

Which pet stores have LCMV-infected rodents? Rodents and other pets from any pet store have some risk of diseases and should be handled with caution. Rodents infected with LCMV may look and act normally. For more information on how to reduce the risk of diseases from a pet, please see the CDC Healthy Pets Web site: www.cdc.gov/healthypets.

What should I do if I no longer want my pet rodent? People who have mice, hamsters or other rodents from pet stores should not return their animals to the stores. People who no longer wish to keep their pet rodent should consult a veterinarian.

Can I release my pet rodent into the wild? No. Pet rodents should never be released into the wild. This is not humane and is illegal in many states. Pet rodents often starve or are killed by predators. Many pet rodents are not native species to North America. If the animal does survive in the wild, it could become a pest, endanger native wildlife, or damage the normal ecosystem.

Can I have my pet rodent tested for LCMV? Testing on live rodents can be inaccurate and misleading. Reliable testing requires the animal to be killed. Always assume that pet animals are capable of spreading disease. Follow precautions as described on CDC's Healthy Pets Web site (www.cdc.gov/healthypets) when handling any pets.

How is LCMV prevented?

You can avoid being exposed to LCMV by doing the following:

Avoid contact with wild rodents.

Seal rodent holes or gaps in your home with steel wool, lath metal, or caulk.

Trap rats and mice that get into your home. Dispose of them by double-bagging and putting in the trash.

Remove food and nesting materials that may attract rodents.

Take extra precautions when handling pet rodents and their cages and bedding.

Always wash your hands with soap and water (and watch young children to make sure they wash their hands) after handling animals, cages or bedding.

Keep rodent cages clean; change the bedding often.

Clean the cage in a well-ventilated area or outside.

Never kiss pet rodents or hold them close to your face.

Pregnant women or people with weak immune systems should avoid all contact with rodents including being in the same room where a rodent lives.

If you use frozen rodents to feed another pet always wear plastic gloves when handling the rodents and wash your hands when you are done.